Enhanced IP phone operation

ABSTRACT

An enhanced IP telephone taking advantage of the many call-related functions provided by existing PBX systems. The enhanced IP telephone includes a thin computer telephony integration (CTI) client transmitting to a CTI server a command associated with a particular call-related function provided by a PBX unit. The CTI server translates the command to a PBX command, and transmits the PBX command to the PBX unit for providing the particular call-related function to the enhanced IP telephone. Instead of the thin CTI client, the enhanced IP telephone may include an enhanced IP signaling protocol stack for accessing the PBX functionality using its signaling protocol. A CTI translator translates the enhanced signaling command to a CTI command for transmitting to the CTI server.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. provisionalapplication No. 60/308,373 filed on Jul. 27, 2001, the content of whichis incorporated herein by reference.

FIELD OF THE INVENTION

[0002] This invention relates generally to internet telephony, and moreparticularly, to internet protocol telephones enhanced withfunctionality provided by existing private branch exchange systems.

BACKGROUND OF THE INVENTION

[0003] Internet protocol (IP) telephones used for Internet telephony viasignaling protocols such as, H.323 or Session Initiation Protocol (SIP),already exist in the prior art. Although these signaling protocols maymake some provisions for additional functionality, such as multipartyconferencing with other SIP and H.323 devices, they do not takeadvantage of the powerful existing functionality already found withinmost private branch exchange (PBX) systems. PBX systems provide suchfunctionality as automatic call distribution, messaging, voice mail,conferencing, call hold, dial-by-name, and the like. Existing Internettelephony signaling protocols do not include specific provisions foraccessing such PBX functionality. Specifically, signaling protocols suchas H.323 and SIP have been designed to work without the use of a PBX.

[0004] The existence of Computer Telephony Integration (CTI) technologydoes not aid in providing PBX functionality to IP phones. Generallyspeaking, CTI is a technology through which computers add intelligenceto telephone networks. CTI is typically applied to a personal computer(PC) with an associated standard telephone to access the functionalityof a PBX. A CTI client resident within the PC typically exploitsfunctionality residing within the PC, such as ActiveX, OLE, dlls, andthe like, to access the PBX functionality. For example, a call may beinitiated by clicking a name in a contact management PC program insteadof dialing the number on the telephone.

[0005]FIG. 1 is a schematic block diagram of a traditional CTI systemconventional in the art. The system includes a CTI-enabled desktop 10including a PC and a traditional telephone set 14. A softwareapplication 18 resident in the PC 12 is used to access a functionalityprovided by a PBX 20 via a CTI client 16 also resident in the PC. TheCTI client transmits commands to a CTI server 22 via an internetprotocol (IP) network 24 associated with the accessed functionality. TheCTI server 22 receives the CTI commands from the PC 12, translates themto PBX commands, and transmits the PBX commands to the PBX for invokingan action on the PBX 20. Communication ensues with the telephone set 14via the PBX 20 over a telephone network 26. Existing CTI architectures,however, are not applicable to IP telephones.

[0006] One approach in allowing IP phones to utilize the existing PBXfunctionality is PBX redesign. PBX redesign exposes the internalfeatures of the PBX to vendor-specific IP phones, allowing IP phones tointeract directly with the PBX without intermediate servers.Unfortunately, PBX redesign and vendor-specific IP phones have thefollowing limitations. First, with PBX redesign, an enterprise may begenerally forced to only use the vendor-specific IP phone with thevendor-specific PBX. As such, customer choice may be eliminated,severely impacting an enterprise migration plan. For example, anenterprise may have multiple types of PBXs and may wish to decouple thechoice of the IP phone from the types of existing or future PBX systems.

[0007] Second, with PBX redesign, many of the vendor-specific IP phonesmay be able to make/place calls to/from the PBX itself, but not fromother standardized IP phones and IP voice gateways. Third, for thevendor to make changes to the internal PBX system, the PBX system mayhave to be modified to expose the functionality to IP clients. This mayrequire substantial development effort on the part of the vendor and mayfurther require each enterprise to install the modified PBX system.

[0008] Consequently, what is needed is a solution that exposes the PBXfunctionality that is typically associated with custom vendor digitalsets or CTI-based PC desktop applications to IP phone clients.Specifically, a solution is needed that enhances IP phone clients withpowerful functionality already resident within many existing PBXsystems.

SUMMARY OF THE INVENTION

[0009] It should be appreciated, therefore, that the present systemsignificantly enhances and simplifies the enterprise migration path toenable IP phones to access PBX functionality with existing PBX and IPnetwork infrastructure. No special PBX units nor PBX redesign isrequired to provide the PBX functionality to the IP phones.

DESCRIPTION OF THE DRAWINGS

[0010] These and other features, aspects and advantages of the presentinvention will be more fully understood when considered with respect tothe following detailed description, appended claims, and accompanyingdrawings where:

[0011]FIG. 1 is a schematic block diagram of a traditional CTI systemconventional in the art;

[0012]FIG. 2 is a schematic block diagram of a system for providing PBXfunctionality to an IP telephone according to one embodiment of theinvention;

[0013]FIG. 3 is a flow diagram of a process for invoking PBXfunctionality from an IP telephone according to one embodiment of theinvention;

[0014]FIG. 4 is a schematic block diagram of a system for providing PBXfunctionality to an IP telephone according to another embodiment of theinvention;

[0015]FIG. 5 is a flow diagram of a process for invoking PBXfunctionality from an IP telephone according to the embodimentillustrated in FIG. 4;

[0016]FIG. 6 is a schematic block diagram of a system for providing PBXfunctionality to a wireless IP telephone according to another embodimentof the invention; and

[0017]FIG. 7 is a flow diagram of a process for invoking PBXfunctionality from a wireless IP telephone according to the embodimentillustrated in FIG. 6.

DETAILED DESCRIPTION OF THE SPECIFIC EMBODIMENTS

[0018]FIG. 2 is a schematic block diagram of a system for providing PBXfunctionality to an IP telephone according to one embodiment of theinvention. The system preferably includes an IP client 30 residing inthe IP telephone (not shown). The IP telephone is preferably a dedicatedInternet telephony appliance preferably including a keypad, functionbuttons, handset, display, and an Internet connection. Unlike a generalpurpose PC with Internet telephony capabilities, the IP telephone is adedicated appliance that preferably incorporates the look and feel of atraditional telephone while allowing telephone conversations over an IPnetwork 32.

[0019] The receiving and transmitting of IP telephony calls over the IPnetwork 32 is performed via the IP client through an IP voice gateway 40in a conventional manner. The IP client 30 preferably includes a thinCTI client 34 for communicating with a CTI server 38 over the IP network32. The CTI server 38 accesses functions provided by a PBX 36 and makesit available to the IP client 30 via its CTI client 34. Such PBXfunctions include automatic call distribution, messaging, voice mail,conferencing, call hold, dial-by-name, and the like.

[0020] The thin CTI client 34 is preferably a stripped-down version ofthe conventional CTI client 16 resident in the PC 12. For instance, thethin CTI client need not include graphics and commands specific to theoperating system utilized in the PC 12. Depending on the processingpower and available memory of the IP client 10, however, the thin CTIclient 34 may include all or portions of the excluded portions of aconventional CTI client 16.

[0021] The CTI server 38 may take the form of any conventional CTIserver interacting with conventional CTI clients resident in PCs. Assuch, the CTI server 38 may support conventional CTI protocols such as,for example, CSTA, Genesys CTI, CTConnect, TSAPI, TAPI, and/or the like.According to one embodiment of the invention, the CTI server 38 isdedicated to a particular type of PBX. In another embodiment of theinvention, the CTI server 38 functions with multiple types of PBXs, andis not limited to only one type.

[0022] The PBX 36 and IP voice gateway 40 may similarly take the form ofany conventional PBX unit and IP voice gateway existent in the art. ThePBX 36 is preferably a generic PBX unit, and not a PBX unit customizedto interact with the IP client 30.

[0023] Although in the embodiment illustrated in FIG. 1, the PBX 36 andIP voice gateway 40 are depicted as two separate components of thesystem, a person skilled in the art should recognize that thefunctionality of the two components may reside in a single IP-enabledPBX. Such an IP-enabled PBX preferably provides IP gateway functionalityas well as PBX switching fabric and functionality according toconventional methods.

[0024] In general terms, the thin CTI client 34 transmits a CTI commandto the CTI server 38 via the IP network 32. The CTI command preferablycorresponds to desired functionality to be invoked in the PBX 36.

[0025] The CTI server 38 receives the CTI command over the IP network32. The CTI server 38 preferably converts the CTI command to acorresponding PBX command according to conventional methods, andcommunicates the converted command to the PBX 36. Voice input and outputto/from the PBX 36 is transmitted from/to the IP client 30 via the IPvoice gateway 40 which converts the voice into IP data packets, andtransmits these data packets over the IP network 32.

[0026]FIG. 3 is a flow diagram of a process for invoking PBXfunctionality from an IP telephone according to one embodiment of theinvention. The process starts, and in step 41, a user of the IPtelephone selects a particular PBX functionality. This may beaccomplished for instance, via selection of pre-programmed buttons onthe IP telephone, menu input selection, and/or via any other selectionmethod conventional in the art. For instance, the user of the IPtelephone may select a conference button on the telephone for initiatinga multi-party conference call via the PBX 36.

[0027] In step 42, the thin CTI client 34 preferably translates theselected PBX function to a CTI command using standard conversionmechanisms. In the above example, the selection of the multi-partyconference call button may cause creation of a “CONF” CTI command havingas parameters the telephone numbers of the parties to be conferenced.

[0028] In step 43, the thin CTI client 34 transmits the CTI command tothe CTI server 38 over the IP network 32. In step 44, the CTI server 38translates the CTI command to a PBX command. The PBX command istransmitted to the PBX 36 in step 45. The PBX receives the command andtriggers an appropriate PBX action in step 46. For instance, in theevent that the PBX 36 receives a command to initiate a conference call,the PBX initiates the conference call by placing the appropriatetelephone calls and informing the IP client 30 via the IP voice gateway40 of the status of the call. If successful, voice communication ensuesvia the PBX 36 and IP voice gateway 40 in a conventional manner.

[0029]FIG. 4 is a schematic block diagram of a system for providing PBXfunctionality to an IP telephone according to another embodiment of theinvention. The system preferably includes an IP client 50, CTI server58, PBX 56, and IP voice gateway 60 which may be similar to the IPclient 30, CTI server 38, PBX 36, and IP voice gateway 40 of FIG. 2.Instead of an embedded thin CTI client, however, the IP client 50illustrated in FIG. 4 includes an enhanced IP signaling protocol stack64 for accessing the functionality provided by a PBX 56. Preferably, theenhanced IP signaling protocol stack 64 includes a conventional IPsignaling protocol stack such as, for example, an H.323 protocol stack,SIP protocol stack, or another protocol stack conventional in the art.The protocol stack 64, however, is enhanced with additional signalingcommands for accessing the PBX functionality. The additional signalingcommands allow the IP client 50 to utilize its signaling protocol toaccess the PBX functionality via a CTI server 58 without the need of aseparate CTI client.

[0030] Preferably the system illustrated in FIG. 4 includes a CTItranslator 62 which receives the enhanced signaling command from theenhanced IP signaling protocol stack 64, translates the signalingcommand to a CTI command, and transmits it to the CTI server 58. The CTItranslator 62 may be a software module residing in a stand-alone server,or may be incorporated in existing devices, such as, for example, anH.323 gatekeeper, SIP proxy server, and/or the like.

[0031]FIG. 5 is a flow diagram of a process for invoking PBXfunctionality from an IP telephone according to the embodimentillustrated in FIG. 4. The process starts, and in step 70, a user of theIP telephone selects a particular PBX functionality. This may beaccomplished for instance, via any of the selection mechanisms describedabove with respect to FIG. 3.

[0032] In step 72, the enhanced signaling protocol stack 64 preferablytranslates the selected PBX functionality to an enhanced signalingcommand. In step 74, the enhanced signaling protocol stack transmits theenhanced signaling command to the CTI translator 62 over the IP network52. In step 76, the CTI translator translates the enhanced signalingcommand to a CTI command. The translation may be implemented in anyconventional manner, such as, for example, via a database lookup of thereceived signaling command for retrieval of a corresponding CTI command.

[0033] In step 78, the CTI translator transmits the CTI command to theCTI server 58. In step 80, the CTI server 58 translates the CTI commandto a PBX command. The PBX command is transmitted to the PBX 56 in step82. The PBX receives the command and triggers an appropriate PBX actionin step 84.

[0034]FIG. 6 is a schematic block diagram of a system for providing PBXfunctionality to a wireless IP telephone according to another embodimentof the invention. A person skilled in the art should recognize that thewireless IP telephone may be replaced with a portable digital assistantwith IP telephony functions and/or another wireless IP telephonyappliance conventional in the art.

[0035] The system illustrated in FIG. 6 preferably includes a CTItranslator 102, CTI server 98, PBX 96, and IP voice gateway 100 whichmay be similar to the CTI translator 62, CTI server 58, PBX 56, and IPvoice gateway 60 of FIG. 4. In addition to the above, the systemincludes a wireless IP client 90 communicating with a wireless IP basestation 104. The wireless IP client 90 includes an enhanced IP signalingprotocol stack 94 for accessing the functionality provided by the PBX96. The enhanced IP signaling protocol stack 94 may be similar to theenhanced IP signaling protocol stack 64 of FIG. 4.

[0036] The wireless IP client 90 preferably includes an RF transmitterand antenna 91 for transmitting RF signals associated with commandsgenerated by the enhanced IP signaling protocol stack 94, and thewireless IP base station 104 includes an RF receiver and antenna 93 forreceiving the RF signals.

[0037] A person skilled in the art should recognize that the enhanced IPsignaling protocol stack 94 may be replaced with a thin CTI client (notshown) such as the thin CTI client 34 of FIG. 2. In this scenario, theCTI translator 102 is not necessary since the thin CTI client 34communicates directly with the CTI server 98 for invoking the PBXfunctionality.

[0038]FIG. 7 is a flow diagram of a process for invoking PBXfunctionality from a wireless IP telephone according to the embodimentillustrated in FIG. 6. The process starts, and in step 110, a user ofthe IP wireless device selects a particular PBX functionality. This maybe accomplished for instance, via any of the selection mechanismsdescribed above with respect to FIG. 3.

[0039] In step 112, the enhanced signaling protocol stack 94 preferablytranslates the selected PBX functionality to an enhanced signalingcommand. In step 114, the enhanced signaling protocol stack transmitsthe enhanced signaling command to the wireless IP base station 104 usingRF signals. In step 116, the wireless IP base station 104 transmits theenhanced signaling command to the CTI translator 102 over the IP network92. In step 118, the CTI translator translates the signaling command toa CTI command. The translation may be implemented in any conventionalmanner, such as, for example, via a database lookup of the receivedsignaling command for retrieval of a corresponding CTI command.

[0040] In step 120, the CTI translator transmits the CTI command to theCTI server 98. In step 122, the CTI server 98 translates the CTI commandto a PBX command. The PBX command is transmitted to the PBX 96 in step124. The PBX receives the command and triggers an appropriate PBX actionin step 126.

[0041] Although this invention has been described in certain specificembodiments, those skilled in the art will have no difficulty devisingvariations which in no way depart from the scope and spirit of thepresent invention. It is therefore to be understood that this inventionmay be practiced otherwise than is specifically described. Thus, thepresent embodiments of the invention should be considered in allrespects as illustrative and not restrictive, the scope of the inventionto be indicated by the appended claims and their equivalents rather thanthe foregoing description.

What is claimed is:
 1. An internet protocol (IP) telephony systemcomprising: a voice switching device providing a plurality ofcall-related functions; a server coupled to the voice switching deviceaccessing the plurality of call-related functions; and an IP telephonecoupled to the server, the IP telephone including logic for transmittingto the server a first command associated with a particular call-relatedfunction provided by the voice switching device, the server translatingthe first command to a second command and transmitting the secondcommand to the voice switching device, the voice switching deviceproviding the particular call-related function to the IP telephone inresponse to the second command.
 2. The IP telephony system of claim 1,wherein the voice switching device is a private branch exchange (PBX)unit and the second command is a PBX command.
 3. The IP telephony systemof claim 1, wherein the server is a computer telephony integration (CTI)server and the first command is a CTI command.
 4. The IP telephonysystem of claim 1, wherein the IP telephone is a wireless IP telephone,and the IP telephone transmits the first command via a wireless basestation coupled to the server.
 5. An internet protocol (IP) telephonysystem comprising: a voice switching device providing a plurality ofcall-related functions; a server coupled to the voice switching deviceaccessing the plurality of call-related functions; a translator coupledto the server for translating between a first command and a secondcommand; and an IP telephone coupled to the translator, the IP telephoneincluding logic for transmitting to the translator the first command forinvoking a particular call-related function provided by the voiceswitching device, the translator translating the first command to thesecond command and transmitting the second command to the server, theserver translating the second command to a third command andtransmitting the third command to the voice switching device, the voiceswitching device providing the particular call-related function to theIP telephone in response to the third command.
 6. The IP telephonysystem of claim 5, wherein the translator resides in a stand-aloneserver.
 7. The IP telephony system of claim 5, wherein the translatorresides in a H.323 gatekeeper.
 8. The IP telephony system of claim 5,wherein the translator resides in a proxy server.
 9. The IP telephonysystem of claim 5, wherein the first command is based on a signalingprotocol used by the IP telephone in engaging in IP telephonycommunication.
 10. The IP telephony system of claim 5, wherein theserver is a computer telephony integration (CTI) server and the secondcommand is a CTI command.
 11. The IP telephony system of claim 5,wherein the voice switching device is a private branch exchange (PBX)unit and the third command is a PBX command.
 12. The IP telephony systemof claim 5, wherein the IP telephone is a wireless IP telephone, and theIP telephone transmits the first command via a wireless base stationcoupled to the translator.
 13. In an internet protocol (IP) telephonysystem including a voice switching device providing a plurality ofcall-related functions, a server coupled to the voice switching deviceaccessing the plurality of call-related functions, and an IP telephonecoupled to the server, the IP telephone comprising: an input forallowing a user selection of a particular call-related function providedby the voice switching device; a microprocessor coupled to the input,the microprocessor including logic for receiving the user selection ofthe particular call-related function and translating the selectedfunction into a first command; and an output for transmitting the firstcommand to the server, the server translating the first command into asecond command and transmitting the second command to the voiceswitching device, the voice switching device providing the selectedcall-related function to the IP telephone in response to the secondcommand.
 14. The IP telephone of claim 13, wherein the voice switchingdevice is a private branch exchange (PBX) unit and the second command isa PBX command.
 15. The IP telephone of claim 13, wherein the server is acomputer telephony integration (CTI) server and the first command is aCTI command.
 16. The IF telephone of claim 13, wherein the output is atransmitter for transmitting the first command via wirelesscommunication media, and the transmitter transmits the first command viaa wireless base station coupled to the server.
 17. In an internetprotocol (IP) telephony system including a voice switching deviceproviding a plurality of call-related functions, a server coupled to thevoice switching device accessing the plurality of call-relatedfunctions, a translator coupled to the server for translating between afirst command and a second command, and an IP telephone coupled to thetranslator, the IP telephone comprising: an input for allowing a userselection of a particular call-related function provided by the voiceswitching device; a microprocessor coupled to the input, themicroprocessor including logic for receiving the user selection of theparticular call-related function and translating the selected functioninto a first command; and an output for transmitting the first commandto the translator, the translator translating the first command to thesecond command and transmitting the second command to the server, theserver translating the second command to a third command andtransmitting the third command to the voice switching device, the voiceswitching device providing the selected call-related function to the IPtelephone in response to the third command.
 18. The IP telephone ofclaim 17, wherein the translator resides in a stand-alone server. 19.The IP telephone of claim 17, wherein the translator resides in a H.323gatekeeper.
 20. The IP telephone of claim 17, wherein the translatorresides in a proxy server.
 21. The IP telephone of claim 17, wherein thefirst command is based on a signaling protocol used by the IP telephonein engaging in IP telephony communication.
 22. The IP telephone of claim17, wherein the server is a computer telephony integration (CTI) serverand the second command is a CTI command.
 23. The IP telephone of claim17, wherein the voice switching device is a private branch exchange(PBX) unit and the third command is a PBX command.
 24. The IP telephoneof claim 17, wherein the output is a transmitter for transmitting thefirst command via wireless communication media, and the transmittertransmits the first command via a wireless base station coupled to thetranslator.
 25. In an internet protocol (IP) telephony system includinga voice switching device providing a plurality of call-relatedfunctions, a server coupled to the voice switching device accessing theplurality of call-related functions, and an IP telephone coupled to theserver, a method for IP telephone operation comprising the steps of:receiving a user selection of a particular call-related functionprovided by the voice switching device; translating the selectedfunction into a first command; transmitting the first command to theserver; translating the first command to a second command; transmittingthe second command to the voice switching device; and providing theparticular call-related function to the IP telephone upon receipt of thesecond command.
 26. The method of claim 25, wherein the voice switchingdevice is a private branch exchange (PBX) unit and the second command isa PBX command.
 27. The method of claim 25, wherein the server is acomputer telephony integration (CTI) server and the first command is aCTI command.
 28. The method of claim 25, wherein the step oftransmitting the first command comprises transmitting the first commandusing wireless communication media via a wireless base station coupledto the server.
 29. In an internet protocol (IP) telephony systemincluding a voice switching device providing a plurality of call-relatedfunctions, a server coupled to the voice switching device accessing theplurality of call-related functions, a translator coupled to the serverfor translating between a first command and a second command, and an IPtelephone coupled to the translator, a method for IP telephone operationcomprising the steps of: receiving a user selection of a particularcall-related function provided by the voice switching device;translating the selected function into a first command; transmitting thefirst command to the translator; translating the first command to thesecond command; transmitting the second command to the server;translating the second command to a third command; transmitting thethird command to the voice switching device; and providing the selectedcall-related function to the IP telephone upon receipt of the thirdcommand.
 30. The method of claim 29, wherein the translator resides in astand-alone server.
 31. The method of claim 29, wherein the translatorresides in a H.323 gatekeeper.
 32. The method of claim 29, wherein thetranslator resides in a proxy server.
 33. The method of claim 29,wherein the first command is based on a signaling protocol used by theIP telephone in engaging in IP telephony communication.
 34. The methodof claim 29, wherein the server is a computer telephony integration(CTI) server and the second command is a CTI command.
 35. The method ofclaim 29, wherein the voice switching device is a private branchexchange (PBX) unit and the third command is a PBX command.
 36. Themethod of claim 29, wherein the step of transmitting the first commandcomprises transmitting the first command using wireless communicationmedia via a wireless base station coupled to the translator.